package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {
    @Value("${reggie.path}")
    private String basePath;
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是一个临时文件，如果不转存，请求结束后就会消失
        log.info(file.toString());
        //获取原始文件名,截取文件格式
        String originalFilename = file.getOriginalFilename();
        String substring = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用UUID重新生成文件名，防止文件名重复产生覆盖
        String s = UUID.randomUUID().toString()+substring;
        //创建一个目录对象
        File dir=new File(basePath);
        //判断当前目录是否存在
        if(!dir.exists()){
            dir.mkdirs();
        }
        try {
            file.transferTo(new File(basePath+s));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(s);
    }
    //文件下载
    @GetMapping("/download")
    public void download(String name, HttpServletResponse httpServletResponse) {
        try {
        //输入流，通过输入流读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath+ name));
        //输出流，通过输出流将文件写回浏览器，在浏览器展示图片
            ServletOutputStream outputStream=httpServletResponse.getOutputStream();
            httpServletResponse.setContentType("image/jpeg");
            int len=0;
            byte[] bytes=new byte[1024];
            while ((len=fileInputStream.read(bytes))!=-1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
